Purification of titanium tetrachloride



Patented Feb. 27, 1951 PURIFICATION OF TITANIUM TETRACHLORIDE Edmund S. Nowicke, Niagara Falls, N .Y., assignor to Stauffer Chemical Company, a corporation 01 California No Drawing. Application June 20, 1950,

Serial No. 169,289

This invention relates to the purification of titanium tetrachloride.

Titanium tetrachloride, as generally prepared by chlorination of a titanium containing material such as ilmenite, possesses an undesirable yellow or dark brown color which is largely due to the presence of certain impurities in small amounts, such as iron, vanadium and unidentified organic impurities. In addition, other impurities are present such as silicon. The technical grade of titanium tetrachloride of commerce contains from 0.05 to 0.08 vanadium taken as V.

Various methods have been proposed heretofore for the removal of vanadium, but none of them has been effective in removing the small quantities present. I have discovered that the addition of a relatively small amount of iron pentacarbonyl is effective to form practically instantaneously relatively non-volatile components in the titanium tetrachloride from which the titanium tetrachloride can be readily separated by distillation. Generally, the amount of iron pentacarbonyl required is relatively small, usually varying from about 1 to 5 parts or more per 1,000 parts of titanium tetrachloride by weight. In place of iron pentacarbonyl, one can utilize the carbonyls of nickel and cobalt.

The following example will further illustrate the process of this invention and is set forth by way of illustration and not by way of limitation.

Example-To 1,000 grams of liquid anhydrous titanium tetrachloride of a technical grade containing 0.09% vanadium, 0.0040% silicon and 0.0017% iron, 5 grams of iron pentacarbonyl were added; a ruby colored solution formed whichsoon produced a black precipitate and a slight evolution oi gas. The mixture was slowly heated in a still to degas the titanium tetrachloride. Continued heating distilled colorless titanium tetrachloride containing no vanadium, 0.0012% silicon and 0.0016% iron, the relatively nonvolatile components remaining in the still-pot.

Although the present invention has been described with reference to the specific details of certain embodiments thereof, it is not intended that such details shall be regarded as limitations upon the scope of the invention except insofar as included in the accompanying claims.

I claim:

1. A method of purifying titanium tetrachloride comprising adding a pentacarbonyl of the class consisting of iron pentacarbonyl. nickel pentacarbonyl and cobalt pentacarbonyl to liquid anhydrous titanium tetrachloride, and distilling the titanium tetrachloride to separate it 5 Claims. (Cl. 202-57) 2 from relatively non-volatile components formed upon addition of the pentacarbonyl to the titanium tetrachloride.

2. A method of purifying titanium tetrachloride comprising adding from about 1 to about 5 parts of a pentacarbonyl of the class consisting of iron pentacarbonyl, nickel pentacarbonyl and cobalt pentacarbonyl to about 1,000 parts of liq- .uid anhydrous titanium tetrachloride, and distilling the titanium tetrachloride from relatively non-volatile components formed upon addition of the pentacarbonyl to the titanium tetrachloride.

3. A method of purifying titanium tetrachloride comprising adding from about 1 to about 5 parts iron pentacarbonyl to about 1,000 parts of liquid anhydrous titanium tetrachloride, and distilling the titanium tetrachloride from relatively non-volatile components formed upon addition of the pentacarbonyl.

4. A method of purifying titanium tetrachloride comprising adding from about 1 to about 5 parts of nickel pentacarbonyl to about 1,000 parts of liquid anhydrous titanium tetrachloride, and distilling the titanium tetrachloride from relatively non-volatile components formed upon addition of the pentacarbonyl.

5. A method of purifying titanium tetrachloride comprising adding from about 1 to about5 parts of cobalt pentacarbonyl to about 1,000 parts of liquid anhydrous titanium tetrachloride, and distilling the titanium tetrachloride from relatively non-volatile components formed upon addition of the pentacarbonyl.

EDMUND S. NOWICKE.

REFERENCES CITEE The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,178,685 Gage Nov. 7, 1939 2,207,597 Pechukas July 9, 1940 2,224,061 Pechukas- Dec. 3, 1940 2,230,538 Jenness -2 Feb. 4, 1941 2,344,319 Meister Mar. 14, 1944 2,412,349 Meyers Dec. 10, 1946 2,415,958 Meyers Feb. 18, 1947 2,416,191 Meister Feb. 18, 1947 2,457,917 Nicholson Jan. 4, 1949 2,508,775 Schaumann May 23, 1950 OTHER REFERENCES Revue Universal des Mines: November 15, 1927, pp. -161, Fabrication, Proprietes et Emploi du Fen-Carbonyl." (Copy in scientific Library). 

1. A METHOD OF PURIFYING TITANIUM TETRACHLORIDE COMPRISING ADDING A PENTACARBONYL OF THE CLASS CONSISTING OF IRON PENTACARBONYL, NICKEL PENTACARBONYL AND COBALT PENTACARBONYL TO LIQUID ANHYDROUS TITANIUM TETRACHLORIDE, AND DISTILLING THE TITANIUM TETRACHLORIDE TO SEPARATE IT FROM RELATIVELY NON-VOLATILE COMPONENTS FORMED UPON ADDITION OF THE PENTACARBONYL TO THE TITANIUM TETRACHLORIDE. 